Australia in October 2012

In Brief

October rainfall was generally below to very much below average across the southern half of Australia with small areas recording their lowest October rainfall. A large area of northwestern Western Australia, far northern Queensland, and some other small pockets recorded above- to very-much-above-average rainfall. For Australia as a whole it was the tenth lowest area-averaged October rainfall on record (since 1900).
Maximum temperatures were generally above average for Australia, with most of South Australia, the southern half of Western Australia, and parts of the Top End recording October-averaged maxima in the highest 10 per cent of records. Most of Tasmania, Victoria, the central Northern Territory, and Queensland recorded average maxima while the only region to record below-average maxima was on the central Queensland coast. October minimum temperatures were below average for most of the eastern States and across the north. Most of Western Australia recorded very-much-above-average minima. Minima were generally average across the far north, parts of central Australia, southern Victoria, and Tasmania.

Temperatures

October-averaged maximum temperatures were above average for Australia as a whole. The national anomaly was +1.53 °C. No State or Territory recorded below-average monthly maximum temperatures.
Maximum temperatures were generally above average across the southern half of the mainland and northern Tasmania. Most of South Australia and adjacent parts of New South Wales and Queensland, the southern half of Western Australia and Pilbara, and parts of the northern and eastern Top End recorded minima in the highest 10 per cent of records. Anomalies exceeded 2°C above average in much of this area, with parts of southern Western Australia and the Interior recording maxima more than 3°C above average. Southern Tasmania, Victoria, the central Northern Territory, and Queensland recorded average maxima. The only region to record below-average maxima was on the central Queensland coast, although anomalies here were on only 1 to 2°C below average.

For Australia as a whole, October minimum temperatures were near-median; the national anomaly was −0.05 °C. The eastern mainland States were quite cool; New South Wales recorded its seventh-coolest October minima (1.13°C below average), Queensland and Victoria their eight-coolest (1.06°C and 0.92°C below average, respectively). For Queensland it was the coolest October since 1982, in terms of minima.
Minimum temperatures were below average for most of northern and eastern Australia during October. Large parts of the eastern mainland and northwest were in the lowest 10 per cent of records, with minima more than 3°C below average for parts of New South Wales and the tropical north, reaching more than 4°C below average in small areas of Queensland and the Northern Territory. An area near Rockhampton, in Queensland, recorded its lowest average October minima. Excluding the northeastern part of the State, Western Australia recorded above average minima, with most of the region in the warmest 10 per cent of records. Anomalies of 2 to 3°C above average were widespread. Minima were generally average across the far north, most of central Australia, along the southern coast of Victoria, and across Tasmania.

Areal average temperatures

Maximum Temperature

Minimum Temperature

Rank(out of 63)

Anomaly*(°C)

Comment

Rank(out of 63)

Anomaly*(°C)

Comment

Australia

54

+1.53

28

−0.05

Queensland

46

+0.78

8

−1.06

lowest since 1982

New South Wales

52

+1.74

7

−1.13

Victoria

48

+0.95

8

−0.92

Tasmania

50

+0.73

33

−0.14

South Australia

57.5

+2.38

44

+0.50

Western Australia

57

+1.95

57

+1.39

Northern Territory

51.5

+1.08

12

−1.05

*Anomaly is the departure from the long-term (1961–1990) average.
A fractional rank indicates that the value is tied for that rank.

Rainfall

Rainfall during October was below average for the majority of the Northern Territory, the southern half of the mainland, and Tasmania. Large parts of this region recorded October totals in the lowest 10 per cent of records, with small areas recording their lowest October rainfall. Averaged across southern Australia (i.e. parts of Australia south of 26°S) October rainfall was the lowest on record (records commenced in 1900), while for southwestern Australia (southwest of a line from Jurien Bay to Bremer Bay) it was the seventh-driest October. This follows on from below-average rainfall across southern Australia in both September and August. Averaged over the three months August–October, rainfall in southern Australia was the second-lowest on record. Excluding the southeast, much of South Australia received very little rain, recording an October total 82 per cent below mean (its fifth-driest October), New South Wales was 65 per cent below mean and the Northern Territory 69 per cent below mean. Other states generally received only 35 to 45 per cent of their mean October rainfall. Averaged over Australia, October rainfall was 52% below average, the tenth lowest area-averaged October rainfall in 113 years of record.

Most of northwestern Western Australia recorded above- to very-much-above-average rainfall. It is, however, still typically a dry time of the year for northwestern Western Australia; falls in decile eight and above over much of this area generally reflect totals of 10 to 25 mm, with higher falls in small areas of the central Pilbara and much of the northern Kimberley. Other small pockets of above-average rainfall were recorded on the southern New South Wales coast, the eastern Top End, central and far northern Queensland, reaching highest on record for the tip of the Cape York Peninsula.

Notes

The Monthly Climate Summary is prepared to list the main features of the weather in Australia
using the most timely and accurate information available on the date of publication; it will generally not be updated.

This statement has been prepared based on information available at
12 noon EST on Thursday 1 November 2012.
Some checks have been made on the data, but it is possible that results will change as new information becomes available, especially for rainfall where much more data becomes available as returns are received from volunteers.

Long-term averages in this statement and associated tables are for the period 1961 to 1990 unless otherwise specified.

In the tables, fractional ranks denote tied values.

A new area-averaging method was adopted for rainfall in May 2009. Current and historical totals for Tasmania are substantially higher than under the old scheme, but differences for other states, and nationally, are negligible.
The rankings and departures from mean shown here use the new method.